Electric circuit breaker with compressed fluid blowout



March 14, 1944.

B. M. H. P. .FERMER ELECTRIC CIRCUIT BREAKER WITH COMPRESSED FLUID BLOW-OUT l Filed June 18, 1938 2` Sheets-Sheet 1 March 14, 1944. B M, H, P, FERMER 2,343,917

ELECTRIC CIRCUIT BREAKER wITHCOMPREssED FLUID BLOW-CUT Filed June 18, 1938 C 2 Sheets-Sheet 2 All' Patented Mar. 14, 1944 ELECTRIC CIRCUIT BREAKER WITH COM- PRESSED FLUID BLOWOUT Bernard Mariek Hilaire Paul Fernier, France; vested in the Alien Property dian Lyon, Custo- 1 Application June 18, 1938, Serial No. 214,489 InGermany June 21, 1937 s claims. (c1. 20o-14s) This invention relates to electric circuitA breakers with compressed fluid blowout and has for one of its objects to provide an improved circuit breaker of the aforesaid type.

Another object of the invention is to provide an electric circuit breaker with compressed uid blowout, in whichthe main contacts are dis-v always positioned within an insulating tubular member serving as a conduit for the blast.

The invention and its objects above set forth as well as others which may hereinafter appear, will be clearly understood from the following description, taken in" connection with the accompanying drawings of several embodiments of the invention herein given for illustrative purposes, the true scope of the invention being more particularly pointed out in the appended claims.v

In the drawings:

Fig. 1 is a view, partly in section, of a circuit breaker embodying an illustrative form of the invention, the contacts oi the arc-drawing device being in closed position and the iixed contact of said device being mounted upon a spring;

Fig. 2 is similar to Fig. 1, but shows the contacts of the.arcdrawing device in separated or open position;

Fig. 3 shows a modiiication of the embodiment shown in Fig. l, the movable contact of the arcdrawing device being. mounted upon a spring;

Fig. 4 is similar to Fig. 3, but with the contacts of the arc-drawing device in separated or open position;

Fig. 5. is a view, partly in section, of a circuit breaker embodying another embodiment of the invention, in which both the movable and the fixed contact of the arc-drawing device are mounted upon springs; v

Fig. 6 is a view, partly in section, of a further embodiment oi?V the invention;

Fig. 'I is a perspective view of a special form of oneof the parts belonging to the movable contact of the circuit breaker;

Fig. 8 is a sectional view of a modification of the fixed contact of the arc-drawing device;

Fig. 9 is a view, partly in section of a circuit breaker in which the fixed contact of the arcdrawingdevice is of the type shown in Fig. 8,

Ii (l both contacts of said device being in closed position; and

Fig. 10 shows a modification ofthe construction shown in Fig. 9.

Referring more particularly to Fig. l, the fixed portion of the circuit breaker is mounted upon a hollow insulator l through which the blast is applied. Said blast may be of any suitable fluid, compressed air being herein used. The arcdrawing device comprises two relatively movable contacts; herein one of said contacts is fixed and the other is movable toward and from said fixed contact. The xed contact 2 is located substantially on the longitudinal axis of a tubular member 3 having converging walls 4 of insulating material, said contact 2 havingA its end'surface level with said converging surfaces during the blowing of the arc, so that the latter at the moment it is blown will be in the best position for extinction. In accordance with the invention the main contacts consist of spring pressed contact brushes 5 and are provided outside of said tubular member. The movable contact of the arc-drawing device is shown at 6 and includes tubular means, such as a tube 1 or an annulus ZI, for example, which forms a main contact surrounding saidfmovable contact 6, said tube engaging beneathl the spring pressed contact brushes 5 and surrounding the tubular member when the contacts 2 and 6 are moved into closed position.

It is desirable to diminish the electro-dynamic repulsion existing between the contacts, particularly in the case of circuit breakers with high rupturing power. Those skilled in the art will understand that by electro-dynamic repulsion is meant the repulsive force which occurs between the two contacts when they approach each other and which tends to separate them. To overcome this repulsion the fixed contact 2 may be resiliently mounted, for example, by being backed up by a relatively strong spring 8 to exert a strong pressure or thrust toward the movable contact at the moment of closure of said contacts (Fig. l). Upon separation of said contacts (Fig. 2) said springy will bring said contact 2 into the most favorable position for the blast. Said snring by its action always enables the tube Lto be disengaged from said spring pressed contact brushes 5 before the separation of the contacts 2 and E.

In accordance with the invention the movable contact may be resiliently mounted instead of the fixed contact 2 (Figs. 3 and 4), for example by means of an abutting spring 9 which can thus move said contact 6 substantially axially of said contact tube 1. Said spring 9 abuts at one end against the bottom I of said tube I and at its other end against an abutment II secured to one end of said contact 6 and having a sliding fit in said tube 1, said abutment engaging a iixed stop I2 within said tube when said contacts 2 and 6 are in open or disengaged position, said contact 6 having a sliding iit in said stop I2. The current is supplied to said tube 1 through spring pressed contact brushes I3, a blade I4 serving electrically to connect said tube and said contact 6. Said spring 9 will be compressed when said contacts 2 and 6 are engaged or in closed position and will expand during the separation of said contacts (see Figs. 3 and 4 respectively) In accordance with the invention both the fixed contact 2 and the movable contact 6 may be spring pressed, each as above described, and as shown in Fig. 5. This arrangement has the ad vantage of reducing the stress upon spring 8 and the stroke of said contact 2. Said springs 8 and 9, or either of them, could also be replaced by suitable electro-magnetic or electro-dynamic means, whereby to ensure compensation of the electro-dynamic stresses.

'I'he movable contact tube 1 need not necessai-ily have continuous or solid walls, as above described but may have its walls slotted or provided with openings to reduce weight or to cause it to conform to any shape that may be given to said tubular member 3; it may for example consist of a plurality of spaced parallel members 20 (Fig. '7) which may serve as guides and electrical conductors and which are joined at their ends adjacent the fixed contact 2, to an annulus or ring 2I which surrounds said tubular member 3 and is positioned under the contact brushes 5, when said contacts 2 and 6 are brought into closed position.

It will be apparent to those skilled in the art that said brushes 5, while being outside the tubular member 3 could be so positioned as to engage the interior surface of said movable contact tube 'I at the end of the relative movement of said contacts 2 and 6 to closed position, instead of being outside said contact tube I as previously described. Such a construction is shown in Fig. 6.

In the illustrative embodiments above described, the compressed fiuid (gas or liquid) enters the tubular member 3 axially thereof, and the corresponding main contacts are outside of said member. Figs. 8 and 9 show modified constructions in which 3| indicates one of the contacts of the arc-drawing device, 32 indicates the converging walls and 33 indicates the sleeve through which the blast of compressed iiuid is supplied. Said contact 3| is provided with guides 34 and 35 and with fixed main contacts 36. Said guides 34 extend about said main contacts 36 to form a covering 34a contained entirely within the nonconvergent portion of said tubular member. As the blast of compressed fluid arrives through said lateral sleeve 33 at the bottom of said covering 34a, and preferably at the point where the convergent portion of said tubular member starts,

the blowing of the arc retains its full efficiency. Said contact 3| 0f the arc-drawing means abuts against a strong spring 31 to enable it to have a certain degree of mobility longitudinally, said spring being free from tacts of the arc-drawing tension when the condevice are not in contact (Fig. 8) and is tensioned when they are in Contact (Fig. 9). This spring is useful in that it compensates the stresses ot electro-dynamic repulsion to which said contacts are subjected when they are in contact. On the other hand it enables the end surface 38 of said contact 3| to be disengaged as much as possible at the moment of separation of the contacts of said arc-drawing device, whereby the blowing operation by compressed gas is improved. When the contacts of the arc-drawing device are engaged (Fig. 9), the movable contact 39 of said device engages between the main contacts 36, while the tube 40, positioned about said movable contact, surrounds said tubular member 3a, said tube 40 being provided with a slot 4I into which the compressed fluid supply line 4a enters during the operation. In this case the tube 40 may with advantage be made of insulating material and in fact may be dispensed with. Such a construction is shown in Fig. l0. In the construction shown in Fig. 9, however, the blowing of the arc will be more efiicacious if a continuous passage, such as tube 40, be provided for the compressed fluid. Electro-magnetic or electro-dynamic compensating means may be added to the compensating spring to reenforce the action of the latter.

The invention has been described mainly in its application to pneumatic circuit breakers in which the fixed contact of the arc-drawing device is disposed under the best conditions for the blowing of the arc at the moment of separation of the contacts of said device. It will be apparent that the invention may include a tubular member of any suitable shape, the iixed contact of the arcdrawing device occupying any desired position relatively to said member. Compressed air or any other suitable compressed gas or liquid may be used. Oil has been used with success.

I am aware that the invention may be embodied in other specific forms without departing from its spirit or essential attributes, and I therefore desire the present embodiments to be considered in all respects as illustrative and not restrictive.

I claim:

1. Electric circuit breaker with compressed fluid blowout comprising arc-drawing means including a fixed contact and a movable contact; means to move the latter toward and from said fixed contact; main contacts ydisposed about the direction of movement of said fixed contact and said movable contact and outside of the blowout blast; means to direct a blowout blast of compressed fiuid from said xed contact toward said movable contact; and an insulating tubular member with converging walls always to enclose said fixed contact of said arc-drawing means and through which the blast takes place.

2. Electric circuit breaker with compressed fiuid blowout comprising arc-drawing means including a iixed contact; and va means to move said movable contact movable toward and from said fixed contact; a conductive tube serve as main contact and containing said movable contact and electrically connected to the latter contacts disposed about said fixed contact outside of the blowout blast; means to 'direct a blowout blast from said fixed contact toward said movable contact; and an insulating tubular member lalways to enclose said fixed contact of said arc-drawing means and through which the blast takes Iplace.

3. Electric circuit breaker with compressed fluid blowout comprising arc-drawing means including a xed contact and a movable contact; means to move said movable contact toward and from said fixed contact; tubular means containing said movable contact, said movable contact being Imounted upon a spring within said tubular means; main contacts disposed about the direction of movement of said movable contact and outside of the blowout blast; means to direct a blowout blast of compressed flu-id from said fixed contact toward said movable contact; and yan insulating tubular member always to `enclose said fixed contact of said arc-drawing means and through which the blast takes place.

4. Electric circuit breaker with compressed fluid blowout, comprising arc-drawing means including a movable contact and a fixed contact to cooperate therewith; means to move said movable contact into and out of contact with said cooperating fixed contact; tubular means containing said movable contact and movable with the latter, said tubular means being of electrically conductive material and electrically connected to said movable contact; means including a tubular member of insulating material, always to surround said fixed contact, to direct a blowout blast oi compressed fluid from said fixed contact toward said movable contact; main contacts disposed about said movable contact and `about its cooperating fixed contact, and outside the blowout blast, the main contacts `about said movable contact and those about said cooperating fixed contact contacting with said tubular means when said movable contact Iis moved toward said cooperating fixed contact to contact with the latter.

5. Electric circuit breaker with compressed fluid blowout, comprising arc-drawing means, including a fixed contact and la movable contact cooperating therewith; means to move said movable contact toward and from said fixed -contact to close and break the circuit; main contacts disposed about said fixed contact and said movable contact, land outside of the blowout blast; and means, including an insulating tubular member of converging shape, Valways to enclose said xed contact, to direct a blowout blast from said fixed contact toward said movable contact.

6. Electric circuit breaker with .compressed fluid 4 blowout, comprising arc-drawing means, including a fixed contact and a movable Contact cooperating therewith; means to move said movable contact toward and from said fixed contact to close and break the circuit; matin contacts disposed about said fixed contact and about said movable contact, and outside the blowout blast; means, including an insulating tubular member of converging shape, always to enclose said fixed contact, to direct a blowout blast from said fixed contact toward said movable contact; and la oasing surrounding said main contacts and said fixed contact of said arc-drawing means, and terminating short of the converging portion of said tubular member.

7. Electric circuit breaker with `compressed fluid blowout, comprising arc-drawing means, including a fixed contact and la movable contact to cooperate therewith; means to move said movable contact toward and from said fixed contact to close Kand break the circuit; 'and means, including an insulating ,tubular member, enclosing said fixed contact and provided with converging walls and an opening coaxial with said movable contact and said fixed contact, said tubular member serving to convey the blast of compressed fluid to said fixed and said movable contacts, and being provided with a lateral opening through which said blast is supplied to said tubular member,

8. Electric circuit breaker with compressed fluid blowout, comprising arc-drawing means, including a fixed contact and ya movable contact to cooperate therewith; means to move lsa-id movable contact toward and from said fixed contact to close and break .the circuit; and means. including an insulating tubular member enclosing said fixed contact and lprovided with converging walls and an opening :coaxial with said movable contact and said fixed contact and at the free end of the latter, to convey the blast of compressed fluid to said fixed and said movable contacts, said tubular member being provided with an opening at the junction of the convergent portion of said tubular member with the remainder thereof and through which said blast of oompressed fluid is supplied to said member.

BERNARD MARIE HILAIRE PAUL FERNIER. 

